Electric socket



Sept. 19, 1933. H. B. PARSON ET AL ELECTRIC SOCKET Filed Oct. 13, 1930mism Y l I i i E g i Patented Sept. 19, 1933 NETE@ STATES ELECTRICSOCKET Howard B. Pearson and Franz R. Culver, i

San Francisco, Calif.

Application October 13, 1930. Serial No. 488,393

7 Claims.

This invention relates to electric sockets.

This application is a continuation in part of our co-pendingapplicationfor Sockets and separable electrical connections, Serial No. 463,338,led

June 23,1930.

The primary object of the invention is to provide an electric socketwhich is adapted to hold a plug, or the ferrule of an electric bulb, byengaging a groove or indentation on the ferrule, whereby the ferrule canbe easily and quickly inserted into the socket; means being provided toestablish firm and positive contact between the ferrule or the like andthe electrical conductors of the socket. Particularly, it is an objectof the invention to provide an electric socket to hold a ferrule or thelike element of an electrical connecting element, by means of aplurality of retaining elements adapted to resiliently, but rmly, engagea groove or indentation in the outer periphery of said ferrule, aconductor strip being arranged in the socket, a portion of which isdisposed between one of the retaining elements and the said ferrule,thereby to establish positive electrical contact thereat.

20 Other objects and advantages are to provide an electric socket thatwill be superior in point of simplicity, inexpensiveness ofconstruction, positiveness of operation, and facility and convenience inuse and general eiliciency.

In this specification and the annexed drawing, the invention isillustrated in the form considered t0 be the best, but it is to beunderstood that the invention is not limited to such form. because itmay be embodied in other forms; and it is also to be understood that inand by the claims following the description, it is desired to cover theinvention in whatsoever form it may be embodied.

The invention is clearly illustrated in the accompanying drawingwherein:

Fig. 1 is a sectional view of a socket with a threaded inner shell,constructed in accordance with our invention.

Fig. 2 is a sectional view of our socket, incorporating a smooth innershell.

Fig. 3 is a fragmental view of the socket showing a retaining ball inthe socket.

Fig. 4 is a fragmental sectional View, showing the mounting of aretaining ball on the socket wall, the section being taken on the line4-4 of Fig. 3.

Fig. 5 is a fragmental view of the socket showlng the retaining ballsecured over the conductor strip or finger. r Fig. 6 is a sectional viewtaken on the line 6-6 5 of Fig. 5.

Fig. '7 is a sectional view of a socket constructed in accordance withour invention, with resilient iingers to hold the ferrule and also theconductor strip.

Fig. 8 is a detail plan view of a disc with the 60 resilient retainingelements or fingers shown in Fig. 7.

Fig. 9 is a detail view of a conductor strip used in our socket.

Fig. 10 is a detail side View of a single, separate 65 resilientretaining linger.

Fig. 11 is a sectional view of a modified embodiment of our invention.

In carrying out our invention we make use of an outer socket shell 6,which is extended over an insulating base 7 in the usual manner. On theend 8 of the base 7 is secured the bottom of an inner shell 9 by meansof screws 11. The inner shell may be threaded as in Fig. 1 so as toreceive the usual threaded ferrule of a plug or electric bulb, or it maybe smooth, as the inner shell 12 in Fig. 2.

In the inner shell 9 is inserted the ferrule 13 of a separable,electrical connecting element. The ferrule preferably used in connectionwith the socket or our construction, is the type described in ourafore-mentioned co-pending application. The ferrule 13 has an annulargroove 14 in its outer periphery adjacent the end thereof, whereby theferrule may be gripped by suitable retaining instrumentalities in thesocket.

The embodiment of our invention shown in Fig.

1 includes a plurality of globes or balls 16, each being disposed in aflared aperture 1'? ln the wall of the inner shell 9. An annular springwire 18 extends around the outer periphery of the shell 9 and extendsthrough the balls 16. The ends of the wire 18 overlap each other. Eachend of the wire 18 is bent into a triangular loop 19, between the loops19 is a coil spring 21, dis- 95 posed around the overlapping endportions of the wire 18, so as to force the loops 19 apart from eachother, thereby to tighten the ring formed by the wire 18 and urge theballs 16 inwardly of the shell 9. In this manner the balls 16 are 100resiliently held in position so thata portion of each ball 16 protrudesbeyond the inner periph: ery of the shell and into engagement with thegroove 14 of the ferrule 13.

Alongside the outer periphery of the shell 9 w55 is disposed a conductorstrip or finger 22, an end 'of which is bent at right angles and issecured between the bottom of the shell 9 and the end of the base 7 byone of the screws 11. Adjacent the free end of the strip 22 is formed aconcavo- 110 convex socket 23, the convex side of which protrudes towardthe interior of the shell 9, and into the concaveside of which fits oneof the balls i6. Thus the conductor socket 23 is interposed between therespective ball 16 and the groove 14 of the ferrule 13. The ball 1S,therefore, not only retains the ferrule 13 in the shell 9, but alsopresses the conductor strip socket 23 against the wall oi the .ierrule13, thereby to accomplish positive and perfect electrical contactbetween the conductor strip 22 and the said ferrule 13.

In the embodiment of our invention shown in Fig. 7, the inner shell 24of the socket is smooth and cylindrical. Between the bottom of the shell24 and the end of the base 7 is disposed a conductor disc 25 from theedge of which extend resilient conductor lingers 27 alongside the outerperiphery oi the shell 24, so that the iree ends of the fingers 27 beartoward 'the interior of the shell 24. Adjacent the free end of eachfinger 2'? is formed a socket `28, similar to the afore-de- .scribedsocket 23. A. plurality of apertures 29 provided in the wall of theshell 24, permit the protrusion of the convex sides of the sockets 28into the shell 24 for engagement with the ferrule 13. Adjacent theinside face of one of the lingers 2'7 a conductor linger 31 is secured.The iinger 31 is similar to the afore-described conductor strip 22. Asocket 32 formed adjacent the free end of the, conductor finger 3i is ofsuch size as to receive the convex side of the socket 28 of the adjacentfinger 2'1 therein to be urged thereby into contact withy the groove 14of the i'errule 13. Thus the respective fingers not only retain theferrule 13 in the shell 24, but also establish perfect electricalcontact between the conductor finger 31 and the ferrule 13.

It is to be noted that the holes 33 in the disc 23 are in registry'withthe screw holes in the bottom of the shell 24, so that the disc 26 istightly held in place between the bottom of the shell 24 and the base 7.

Il' desired separate spring fingers 34 may be employed in place of thedisc arrangement, especially in cases where a socket of the standardtype heretofore used, is altered to receive ferrules of the type hereinshown.

The embodiment shown in Fig. 1l, utilizes a plurality of double strips37 disposed around the inner shell 9' of the socket. At least three suchstrips 3'1 are required, equally spaced around the shell circumferenceto hold the ferrule 13 in place. Each strip -37 is bent to form twoseparate fingers 38 and 39. The folded or doubled end 41 of the strip 37is at an angle to the fingers 38 and 39 and is secured between thebottom of the shell 9' and the end of the base of the socket. A securingscrew 11 extends through the said doubled end 41. Each inner finger 39has a cup 42 formed adjacent the free end thereof, Athe convex side ofwhich protrudes beyond the inner face oi the .nger 39 and extendsthrough an aperture 43 into the interior of the shell 9'. The outerfinger 38 has av portion 44 thereof recessed opposite the cup 42. Theouter side of the portion 44 lays against the usual insulating lininginside of the outer shell/not shown. A tapered coil spring 46 isdisposed between the recessed portion 44 and the cup 42. The smaller end0i the spring 46 is within the cup 42, and the wider end thereof bearsoutwardly against the recess of portion 44. Inasmuch as the portion 44bears against the lining of the outer shell of the socket, the force ofthe spring 46 is utilized to urge the cup 42 into the inner shell 9. Itis to be noted that the free end of the linger 38 is bent at an ,angletoward the end of the inner finger 39 thereby to facilitate assembly ofthe socket, One or more of the inner fingers 39 is lined with aconductor lining or finger to conduct negative electricity to theferrule 13. l

In all of the embodiments of our invention the resilient retainingelements act also as contacting elements whereby the respectiveconductor fingers are held in Contact with the respective ferrules. Theelectrical conducting ngers, or linings are made of good conductormetal. The lingers, discs and other resilient retaining elements aremade of high grade steel material, such as clock spring material.

It isto be noted that in the center ci the cud o the insulating base isa positive contact, with which the corresponding central Contact of theferrule is held in engagement. The conductor strips, fingers. andlinings on the retaining elc nient are used as negative contacts to therespective ferrules, the ferrules being, of course, insulated from thecentral positive contacts.

The insertion and removal of the .ferrules into and from the inner shellof the socket i s performed in the manner described in ouraforementioned copending application.

Having thus described this invention, what we claim and desire to secureby Letters Patent is:

l. The combination with a ferrule oi an electric connecting element saidferrule having an indentation on its outer periphery; of an electricsocket, an inner shell adapted to receive the said ferrule therein, aconductor disposed alongside the inner shell. a concavo-convex cupformed a`djacent the free end of the conductor, the convex side of saidcup being disposed in operative relation to said indentation,and'resilient means exertingV a pressure on the concave side of said cupto urge the said convex side into operative engagement with the ferruleindentation.

2. The combination with a conductor ferrule of an electric connectingelement, said ierrule having an annular groove in its outer peripheryadjacent an end thereof; of a socket, an inner shell in the socketadapted to receive said ferrule therein; a conductor strip extendedalongside the inner shell having a concave-convex protrusion formedadjacent the free end thereof in operative relation to the ferrule, saidshell having an aperture therethrough in alignment with the groove inthe ferrule when assembled, the convex side of said protrusion being inalignment with said aperture, and resilient means adjacent the innershell to urge the said protrusion through the said aperture intocontacting engagement with the said groove.

3. The combination with a conductor ferrule of an electric connectingelement, said ferrule having an annular groove in its outer peripheryadjacent an end thereof; of a socket, an inner shell in the socketadapted to receive said ferrule therein: a conductor strip extendedalongside the inner shell having a concavo-convex protrusion formedadjacent the free end thereof in operative relation to the ferrule, saidshell having an aperture therethrough in alignment -with the groove inthe fer rule when assembled, the convex side of said protrusion being inalignment with said aperture. resilient means adjacent the inner shellto urge the said protrusion through the said aperture into contactingengagement with the said groove; a plurality of retaining elementsadjacent the shell adapted to engage the said ferrule groove directly,

and resilient means to urge said retaining element into engagement withthe groove.

4. An electric socket for an electric connecting element comprising anouter shell, an. insulating base in an end of the shell,.an inner shellin the outer shell mounted on the base being adapted to receive the saidelement therein, a conductor strip extended alongside the inner shell, aprojection adjacent the end of the strip adapted to be extended beyondthe inner surface of the inner shell into engagement with said element.a resilient retaining element between the inner and outer shell to urgesaid strip and projection toward the interior of the inner shell, and aconcave socket formed on the side of the strip opposite the projection,said retaining element being adapted to extend into said socket.

5. An electric socket for an electric connecting element comprising anouter shell, an insulating base in an end of the shell, an inner shellin the outer shell mounted on the base being adapted to receive the saidelement therein, a conductor strip extended alongside the inner shell, aprojection adjacent the end of the strip adapted to be extended beyondthe inner surface of the inner shell into engagement with said element,a resilient retaining element between the inner and outer shell to urgesaid strip and projection toward the interior of the inner shell, andl aconcave socket formed on the side of the strip opposite the projection,said retaining element being adapted to extend into said socket, saidretaining element comprising a spring nger having a bent endthereoLsecured between the end of the inner shell and the base, andbeing so formed adjacent its free end as to t into said socket to urgethe strip inwardly.v

6. An electric socket for an electric connecting element comprising anouter shell, an insulating base in an end of the shell, an inner shellin the outer shell mounted on the base being adapted to receive the saidelement therein, a conductor strip extended alongside the inner shell, aprojection adjacent the end of the strip adapted to be extended beyondthe inner surface of the inner shell into engagement with said element;a disc secured between the base and the inner shell,k a plurality ofspring fingers extended from said disc alongside the inner shell, theend of each finger being formed with a projection adapted to extendbeyond the inner periphery of the inner shell to engage said element,said shell being adapted to allow the extension of said projectionsbeyond its inner periphery, one of said fingers being in alignment withsaid strip so as to urge the latter and the projection of the striptherewith against the said element inside of the inner shell. '1. Anelectric socket for an electric connecting element comprising an outershell, an insulating base at an end of the shell, an inner shell in theouter shell related to the base being adapted to receive the saidelement therein, a conductor strip extended alongside the inner shell, aprojec-V tion adjacent the end of the strip adapted to be extendedbeyond the inner surface of the inner shell into engagement with saidelement, a. plurality of apertures through the periphery of the innershell, a retaining element disposed in each aperture, resilient means tohold the retaining element in position so that the said elements areextended into said shell to engage said element, said conductor striphaving a projected socket formed therein in alignment with one of saidretaining elements to be disposed between said retaining element,thereby to be pressed into contact with the said connecting element.

HOWARD B. PEARSON. F. R. CULVER'

